1. Technical Field
The present invention relates to a magnetism measurement apparatus, a gas cell, a method for manufacturing the magnetism measurement apparatus, and a method for manufacturing the gas cell.
2. Related Art
There is a known optically pumping magnetism measurement apparatus that irradiates a gas cell having an alkali metal gas enclosed therein with linearly polarized light and measures a magnetic field in accordance with the angle of rotation of the polarization plane. JP-A-2012-183290 discloses a magnetism measurement apparatus including a gas cell that is made of glass and accommodates an ampule formed of a glass tube having an alkali metal enclosed in a hollow portion of the tube. In the magnetism measurement apparatus, the ampule is so irradiated with laser light that a through hole is formed through the ampule (glass tube), and the alkali metal in the ampule is evaporated so that the cell is filled with the vapor (gas) of the alkali metal.
When the concentration of the alkali metal gas in the gas cell is low or unstable, the performance of the magnetism measurement apparatus decreases, resulting in imprecise measurement in some cases or the magnetism measurement apparatus does not function in other cases. It is therefore required to provide a magnetism measurement apparatus that can be stably manufactured with variation in the concentration of the alkali metal gas in the gas cell suppressed and is therefore capable of highly precise measurement and further provide a method for manufacturing the magnetism measurement apparatus.